1. Technical Field
The present invention relates generally to client-server computing over a computer network such as the Internet and, in particular, to a method for dynamically generating Web pages at a Web server in response to received HTTP requests.
2. Description of the Related Art
The World Wide Web is the Internet's multimedia information retrieval system. In the Web environment, client machines effect transactions to Web servers using the Hypertext Transfer Protocol (HTTP), which is a known application protocol providing users access to files (e.g., text, graphics, images, sound, video, etc.) using a standard page description language known as Hypertext Markup Language (HTML). HTML provides basic document formatting and allows the developer to specify "links" to other servers and files. In the Internet paradigm, a network path to a server is identified by a so-called Uniform Resource Locator (URL) having a special syntax for defining a network connection. Use of an HTML-compatible browser (e.g., Netscape Navigator or Microsoft Internet Explorer) at a client machine involves specification of a link via the URL.
When the user of the browser specifies a link, the client issues a request to a naming service to map a hostname (in the URL) to a particular network IP address at which the server is located. The naming service returns a list of one or more IP addresses that can respond to the request. Using one of the IP addresses, the browser establishes a connection to a server. If the server is available, it returns a Web page.
To facilitate further navigation, a Web page typically includes one or more hypertext references known as "anchors" or "links". In HTML, each anchor is commonly delineated by a markup language "tag" set "&lt;A href "pathname"&gt;&lt;/a&gt;", where "pathname" is the path information identifying the location of the linked page or object. A &lt;href&gt; tag, however, may identify a server that no longer supports the object content or is otherwise performing poorly against a given metric. If the user later activates the link, he or she may not be able to navigate to the desired location, or such navigation may be unacceptably slow.
It would be highly desirable to be able to assure a user that, when a given Web page is returned from a Web server, the anchor references are valid at that time. The present invention provides a solution to this problem.